The present invention relates to a connector for use in connecting a handle to a domestic utensil or a hand tool, for example a brush head.
In a conventional brush or broom of a type formed of synthetic materials the handle is commonly secured to the head by a screw fit, a lower end of the handle being formed with a male threaded part which fits into a female threaded socket on the brush head. Whilst providing an adequate connection there is inevitably a degree of flexure of the screw-fitted parts, which results in the gradual unscrewing of the connection during continued use, and eventual damage to the threaded connection, and if the threaded parts are formed of poorly constructed or cheaply moulded parts, one or other of the connected parts may crack or split so that the brush becomes unusable.
Various attempts have been provided to design a more robust connection. In one of the more successful, the female connector part has a socket end defined by a plurality of split fingers with an outer circumferential thread and a locking ring provided. As the locking ring is screwed down over the socket the fingers are deformed together, tightening their grip on the male part therein. Although this arrangement provides some benefit, it still suffers problems of flexure, and is more complicated and hence expensive to mould.
The present invention seeks to provide a connector which overcomes these drawbacks.
According to a first aspect of the present invention there is provided a connector for securing a handle to a utensil comprising a male part having a threaded portion adjacent the free end of said male part thereof which joins a shaft portion of greater diameter than that of the threaded portion, a female socket part with a complementary internal screw thread, and a support collar joined to the female socket to overlie the socket and defining an opening for receiving the male part through which the shaft portion extends wherein the support collar opening is slightly smaller than the shaft portion whereby there is an interference fit therebetween when the male and female parts are engaged.
The support collar is able to provide a tight support against relative lateral movement or flexing of the connection, thereby greatly improving the strength of the connection. Only a single action is required to make the connection, that is screwing the parts together, and no separate locking ring is needed.
In the preferred embodiment the support collar is joined to the socket by a connecting bridge which comprises a bent web of elongate section which is able to flex towards the socket part.
The precise shape and dimension of the male part is important for providing a particularly effective rigid connection. In a further aspect the invention provides a connector for securing a handle to a utensil comprising a male part having a threaded portion adjacent the free end of said male part thereof which joins a shaft portion of greater diameter than that of the threaded portion through a shoulder, a female socket part with a complementary internal screw thread, and a support collar jointed to the female socket by a flexible connecting bridge to overlie the socket and defining an opening for receiving the male part through which the shaft portion extends and which tightly engages the shaft portion when the male and female parts are engaged wherein the support collar opening is dimensioned relative to the shaft portion of the male connector such that as the male part is screwed into the female socket part the shoulder engages an edge of the opening of the support collar and urges the support collar down towards the socket part, thereby deforming said opening. The angle and dimension of the shoulder is selected such that on continued insertion the support collar bends down until a portion thereof abuts the socket part, and such that continued screwing in of the male part moves the shoulder portion through the opening until a reaction force of the connection bridge forces the collar over the shoulder onto the shaft.
The connector may be secured to parts of a domestic utensil such as a brush, for example, the male part may be secured to a handle and the female part to a brush head, or the connector parts may be integrally formed with the parts of the brush.